Aircraft undercarriages are known that are hinge-mounted to a structure of the aircraft to move between a deployed position and a retracted position. In the deployed position, the undercarriage is generally stabilized by a foldable brace that is coupled to the undercarriage and to the structure of the aircraft, and that comprises two elements that are hinged to each other and that are held in an aligned position. In order to enable the undercarriage to be raised, the elements of the foldable brace are moved out of alignment in order to enable the undercarriage to pivot towards its retracted position under the action of a drive actuator.
Undercarriages are known in which the drive actuator is a rotary actuator acting on one of the elements of the foldable brace. The drive actuator is generally fastened to the structure of the aircraft and drives one of the elements of the foldable brace either directly, or else via a linkage. The structure of the aircraft then needs to be designed so as to take up the forces and the torque that are developed by the drive actuator when driving the undercarriage.